Jerry Jones isn’t happy with NFL commissioner Roger Goodell anymore, and the feud might get ugly for the NFL.

According to the New York Times, the Dallas Cowboys owner has hired lawyer David Boies (who finds himself involved in the Harvey Weinstein scandal) and has threatened to sue the league and some team owners over the negotiations over Goodell’s contract extension. The Times reported there was a conference call with Jones and the NFL’s compensation committee — owners from the Chiefs, Falcons, Giants, Patriots, Steelers and Texans — and Jones told them legal papers were drawn up and would be served this Friday unless the committee drops its plan to give Goodell an extension. Goodell’s contract expires after the 2018 season.

While nothing has happened yet, it’s a growing issue for the league.

While there are plenty of criticisms of Goodell, including questions about television ratings and much of the attention for this season on player anthem protests, it’s easy to wonder if Jones is getting back at Goodell for suspending his star running back Ezekiel Elliott. The NFL suspended Elliott six games in August over an alleged domestic violence incident, after Jones was adamant there was no evidence against him. Elliott has continued to play while the issue works its way through the courts, but Jones still seems to have turned on Goodell over the suspension. The New York Times report said the threats over Goodell’s extension “stems from Jones’s anger over the commissioner’s suspending” of Elliott.

Goodell has faced heat from the outside, but it has been rare to hear any owners rip him publicly. The league has grown to unprecedented financial success under Goodell. But with so many negative off-field stories dominating the action on the field recently, the tide seems to be turning.

Goodell and the NFL did what they thought was right in suspending Elliott. In doing so, it seems the commissioner made a very powerful enemy.